PROJECT SUMMARY/ABSTRACT While the rate of neonatal abstinence syndrome has reached a staggering 6.5 per 1,000 births nationwide, the short- and long-term effects of in-utero opioid exposure are far from clear. We lack fundamental knowledge of neurotypical neonatal development and struggle to disentangle the effect of opioid exposure from other protective and risk factors impacting infant health. The fetal stage of brain development is a critical period when foundational aspects of brain structure and function are being established. In addition, postnatal brain development and specialization are shaped by environmental experiences thus allowing maturation to be influenced by lifestyle factors associated with opioid use. This Phase I project will plan for a large scale, multi- site research study to prospectively examine human brain, cognitive, behavioral, social, and emotional development beginning prenatally through childhood. The University of Pittsburgh is one of four linked sites including Oregon Health and Sciences University, New York University and the University of Vermont that will address key challenges critical to the success of the planned Phase II study. Aim 1 will develop, implement and evaluate innovative recruitment and retention strategies for high-risk populations through a longitudinal survey of 150 pregnant women per site (n=600 across sites), half of whom are opioid using. Aim 2 will implement a multi-site, standardized, longitudinal research protocol by enrolling 20 pregnant women per site (n=80 across sites), half of whom are opioid using. This prospective longitudinal study will collect fetal and neonatal multimodal MRI, biospecimens, and maternal psychosocial and health assessments. Aim 3 will evaluate data acquisition, processing, and statistical considerations to maximize data quality, usability, and integration across sites. We will test the efficacy of (A) real-time motion monitoring/quality assessment for improving overall data quality and (B) time-savings versus MRI quality using new acceleration sequence protocols. This approach will inform and set a strong foundation for a comprehensive and effective Phase II research plan. The University of Pittsburgh site is led by a highly productive, NIH-funded investigative team with multidisciplinary expertise in substance use (Krans, Bogen), pregnancy (Krans), and fetal, neonatal, and pediatric neuroimaging (Luna, Panigrahy). Specifically, our team has established study protocols that yield excellent recruitment (~76%) and retention (~74%) rates among opioid using pregnant women, has substantial experience with imaging the immature brain (fetal/neonatal) and is a leader in developmental cognitive neuroscience using multimodal imaging to investigate neural mechanisms underlying neurocognitive development through adolescence. We will leverage our on-going, NIH-funded, multi-center neuroimaging studies to provide imaging harmonization techniques and assist with the development of structural fetal brain and placental imaging pipeline for all linked sites to assistant with development of Phase II protocol. Further, we will pilot innovative studies of age-related Iron deposition and quantitative fetal MR spectroscopy.